An intelligent street lamp dimming system based on power line signal transmission

Abstract

The present application relates to the technical field of intelligent lighting control, and discloses an intelligent street lamp dimming system based on power line signal transmission, including: a sensor module for real-time acquisition of multi-dimensional sensing data corresponding to the position of the street lamp; a regional control terminal connected to the sensor module, receiving and uploading multi-dimensional sensing data through the power line; a central controller that performs a dynamic area division algorithm on the street lamps according to the multi-dimensional sensing data to divide independent control areas, and sends a street lamp brightness adjustment instruction according to the brightness optimization model; a dimming drive module that receives the brightness adjustment instruction transmitted through the power line and adjusts the brightness of the street lamps in the corresponding independent control area; through the analysis and fusion of multi-dimensional sensing data, dynamic grouping of street lamps can be realized, so as to achieve regional dynamic dimming, which can not only optimize energy efficiency but also reduce the full life cycle operation cost of street lamps.

Description

Technical Field

[0001] This application relates to the technical field of intelligent lighting control, and in particular, to an intelligent street lamp dimming system based on power line signal transmission. Background Art

[0002] Urban roads, highway lighting, etc. play a very important role in the traffic, public security, and beautification of a city. They are a window of a city and an important part of the city's infrastructure. If street lamps cannot work properly, it will not only affect the city's image but also easily lead to traffic safety accidents.

[0003] As an important part of the infrastructure, the energy consumption of the urban road lighting system accounts for about 2.5% - 3% of the global electricity consumption. Traditional street lamps generally use high-pressure sodium lamps or fixed-brightness LED light sources and operate in a static grouping or simple time-sequence control mode, that is, a timer is installed in the street lamp distribution box to turn on and off the lights automatically according to a predetermined time; while some landscape lamp switches are usually manually controlled. Faults during operation can only be discovered when the inspection personnel arrive at the scene, so it is difficult to achieve timely communication and maintenance.

[0004] According to statistics from the International Energy Agency (IEA), due to the inability of traditional street lamp systems to dynamically respond to traffic demands, the average redundant lighting time at night reaches 4 - 6 hours, resulting in about 35% - 50% of ineffective energy consumption. Typical manifestations are:

[0005] Full power operation is still maintained during low-traffic periods (such as 1 - 5 am).

[0006] Adjacent road sections have the same brightness due to significant differences in traffic flow (such as the junction of a commercial area and an industrial area).

[0007] Typical case: Measured data of the main road in a provincial capital city shows that under the fixed-brightness mode, the actual lighting demand during the early morning hours is only 40% of the design value, but the system still operates at 100% power, wasting more than 800 kWh of electric energy per day.

[0008] Current mainstream solutions (such as CN112867205A, US20210307089A1) mostly rely on a single parameter to trigger dimming: Time control mode: Only adjust the brightness according to the preset time period and cannot adapt to sudden traffic changes (such as the end of a large event); Basic sensor mode: Use a single microwave radar or photosensitive sensor with a high misjudgment rate (such as a bird triggering the radar signal); Fixed threshold zoning: Divide the control area based on administrative boundaries or fixed lengths (such as every 500 meters as a group), resulting in the split control of cross-regional vehicle flows.

[0009] In summary, there is an urgent need for a solution that integrates highly reliable communication, multi-modal sensing, and intelligent decision-making to achieve refined dynamic dimming of street lamp systems without the need for additional wiring. Summary of the Invention

[0010] In order to achieve refined dynamic dimming of street lamp systems, this application provides an intelligent street lamp dimming system based on power line signal transmission, adopting the following technical solutions:

[0011] An intelligent street lamp dimming system based on power line signal transmission includes:

[0012] A sensor module for real-time acquisition of multi-dimensional sensing data corresponding to the position of street lamps.

[0013] A regional control terminal connected to the sensor module, receiving and uploading the multi-dimensional sensing data through the power line.

[0014] A central controller that performs dynamic area division algorithm on street lamps according to the multi-dimensional sensing data to divide independent control areas, and sends street lamp brightness adjustment instructions according to the brightness optimization model.

[0015] A dimming drive module that receives the brightness adjustment instructions transmitted through the power line and adjusts the brightness of the street lamps in the corresponding independent control area.

[0016] Among them, the multi-dimensional sensing data includes the current time, traffic flow density, pedestrian flow density, vehicle speed, vehicle classification, as well as pedestrian speed and pedestrian classification; the dynamic area division algorithm includes:

[0017] Real-time clustering of adjacent street lamps into independent control areas according to the spatial distribution of traffic flow density and pedestrian flow density.

[0018] By adopting the above technical solutions, this application can achieve dynamic grouping of street lamps through the analysis and fusion of multi-dimensional sensing data, thereby realizing regional dynamic dimming, greatly reducing the redundant lighting area, reducing the operation time of lamps at full power or high power, not only optimizing energy efficiency but also reducing the full-life cycle operation cost of street lamps. At the same time, communication based on power transmission lines can, on the one hand, reduce the line transformation cost, and on the other hand, can greatly improve the anti-interference performance during long-distance transmission compared with mainstream wireless communication solutions.

[0019] Optionally, the dynamic area division algorithm includes:

[0020] Obtain the geographical locations and corresponding numbers of all street lamps.

[0021] Calculate the similarity between street lamp i and adjacent street lamp j within a limited area with a diameter of R ;

[0022] ;

[0023] Wherein, the center of the defined area coincides with the position of the street lamp i. is the straight-line distance between the street lamp i and the street lamp j. is the value of the k-th type of sensing data configured on the street lamp i. is the value of the k-th type of sensing data configured on the street lamp j. is the maximum value corresponding to the k-th type of sensing data, and z is the total number of types of sensing data.

[0024] Within the defined area, the similarity greater than or equal to the specified similarity threshold of the street lamps are classified into the independent control area.

[0025] By adopting the above technical solution, the degree of difference in the environments where adjacent street lamps are located can be determined through the calculation of the similarity . The greater the similarity , the smaller the environmental difference between adjacent street lamps. Therefore, the same brightness adjustment instruction should be adopted, so that it is not necessary to control each street lamp individually, reducing the control management cost and also reducing the waste of electric energy. Moreover, it can give passing cars and pedestrians the feeling of the street lamps following them, ensuring the normal use of users.

[0026] Optionally, the dynamic area division algorithm includes:

[0027] Configure a specified path length , and obtain the number m of street lamp division areas on the specified path length ;

[0028] If , then adjust the value of the specified similarity threshold until ;

[0029] Wherein, , is the minimum division number, and is the preset standard path length.

[0030] By adopting the above technical solution, unnecessary or excessive dynamic area division numbers can be reduced, and the management and control cost can be reduced.

[0031] Optionally, the method for obtaining the brightness adjustment instruction includes:

[0032] ;

[0033] ;

[0034] Wherein, is the real-time traffic flow, is the pedestrian flow density, is the theoretical maximum traffic flow, is the theoretical maximum pedestrian flow density, , is the average vehicle speed, is the vehicle speed limit value, is the average pedestrian speed, is the theoretical maximum walking speed of pedestrians, is the preset demarcation time point, is the specified value, is the lowest reference brightness value, is the dynamic weight, which is inversely proportional to the illuminance and directly proportional to the rainfall and fog index, is the dynamic fine-tuning weight, is the natural constant, t is the current time point, , , , are the specified weighting coefficients of the corresponding items respectively.

[0035] Optionally, the sensor module includes:

[0036] A geomagnetic sensor for detecting vehicle presence judgment and vehicle speed estimation;

[0037] A pyroelectric infrared sensor for sensing the change in infrared intensity caused by human body heat radiation and enhancing the signal with a Fresnel lens;

[0038] An embedded camera for assisting in visual verification and anomaly detection of traffic flow density.

[0039] Optionally, it further includes:

[0040] A cloud server, deploying a highly available cluster server, running a digital twin engine, synchronizing urban multi-dimensional data in real time, and synchronously accessing meteorological data, where the meteorological data includes illuminance, rainfall, and fog index.

[0041] Optionally, the cloud server deploys a target detection model, and the target detection model performs visual verification and anomaly detection based on the video data obtained by the embedded camera;

[0042] The visual verification includes: classifying and bounding the target objects in the detection area through the target detection model, and determining the number of target objects according to the number of bounding boxes;

[0043] The anomaly detection includes crowd gathering and traffic accidents;

[0044] The judgment rules for crowd gathering include:

[0045] The density of the flow of people exceeds the specified threshold of the density of the flow of people, and the number of detection frames determined to be human bodies is greater than the specified threshold of the number of people;

[0046] The judgment rules for traffic accidents include:

[0047] Abnormal vehicle attitude: Aspect ratio mutation > 20%;

[0048] Discontinuous movement: Acceleration > 3m / s²;

[0049] Multi-object interaction: IoU of multiple detection frames > 0.6 for 3 seconds;

[0050] If any of the above is satisfied, it is determined that a traffic accident has occurred.

[0051] Optionally, the dimming drive module adopts a hybrid dimming architecture: integrating PWM high-frequency chopping and CCR linear regulation, and the lamps used by the street lamps integrate at least 4 independent LED lamp strings;

[0052] Channel 1: Color temperature 5000K, maximum current 1.2A, providing main road lighting;

[0053] Channel 2: Color temperature 3000K, maximum current 0.8A, providing warm light for the sidewalk;

[0054] Channel 3: Color temperature 6500K, maximum current 1.5A, providing emergency high brightness;

[0055] Channel 4: Color temperature RGBW, maximum current 0.5A per color, providing landscape interaction.

[0056] Optionally, the sensor module includes a power line carrier communication module responsible for communicating with the area control terminal using the high-speed power line carrier technology HPLC;

[0057] The power line carrier communication module, the physical layer supports OFDM modulation, the number of subcarriers ≥ 512, the symbol rate is 10ksps, and the data link layer supports the TDMA / CSMA hybrid access mode, and the time slot length is 100ms;

[0058] The power line carrier communication module adopts an adaptive frequency band switching technology, supports full frequency band coverage of 0.7 - 12MHz, and divides it into three sub-frequency bands:

[0059] Low frequency band: 0.7 - 3MHz (except for the value of 3MHz, the anti-attenuation performance ≥ 85dB);

[0060] Medium frequency band: 3 - 6MHz (except for the value of 6MHz, the default communication frequency band);

[0061] High frequency band: 6 - 12 MHz (short - distance high - speed transmission);

[0062] Monitor the channel quality in real - time through the spectrum sensing algorithm, dynamically select the optimal sub - band, and independently set the power spectral density in each sub - band.

[0063] Optionally, the method for obtaining the minimum reference brightness value includes:

[0064] ;

[0065] wherein, is the bad weather coefficient, is a preset dynamic coefficient function associated with the bad weather coefficient, is related to the road level corresponding reference brightness value.

[0066] In summary, the present application includes at least one of the following beneficial technical effects:

[0067] 1. Through the analysis and fusion of multi - dimensional sensing data, the present application can achieve dynamic grouping of street lamps, thereby realizing regional dynamic dimming, greatly reducing the redundant lighting area, reducing the operation time of lamps at full power or high power, optimizing energy efficiency, reducing the full - life - cycle operation cost of street lamps. At the same time, communicating based on the power transmission line can, on the one hand, reduce the line transformation cost, and on the other hand, can greatly improve the anti - interference performance during long - distance transmission compared with the mainstream wireless communication solutions.

[0068] 2. By calculating the similarity , the difference degree of the environments where adjacent street lamps are located can be determined. The larger the similarity , the smaller the environmental difference between adjacent street lamps. Therefore, the same brightness adjustment instruction should be adopted, thus eliminating the need for individual control of each street lamp, reducing the control and management cost and power waste, and creating a sense of street - lamp follow - up for passing cars and pedestrians, ensuring the normal use of users.

[0069] 3. Relying on the low - latency characteristics of power - line communication (PLC) and combined with the brightness adjustment instruction, the present application can dynamically adjust the brightness according to the requirements of different time periods, real - time traffic data, weather data, and other special events, achieving a full - link fast response from perception to execution and optimizing the lighting management efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 is a schematic diagram of the module connection of the intelligent street - lamp dimming system in the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0071] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings.

[0072] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0073] An intelligent street lamp dimming system based on power line signal transmission is disclosed in an embodiment of the present application, as Figure 1 shown, including:

[0074] A sensor module for real-time acquisition of multi-dimensional sensing data corresponding to the position of the street lamp.

[0075] Specifically, the sensor module in this embodiment includes a power line carrier communication module responsible for communicating with the area control terminal using the high-speed power line carrier technology HPLC; this power line carrier communication module supports OFDM modulation at the physical layer, with the number of subcarriers ≥512, a symbol rate of 10ksps, and its data link layer supports a TDMA / CSMA hybrid access mode with a time slot length of 100ms; the power line carrier communication module uses an adaptive frequency band switching technology, supports full frequency band coverage from 0.7 to 12MHz, and divides it into three sub-bands:

[0076] Low frequency band: 0.7 - 3MHz (except for the value of 3MHz, the anti-attenuation performance ≥85dB);

[0077] Medium frequency band: 3 - 6MHz (except for the value of 6MHz, the default communication frequency band);

[0078] High frequency band: 6 - 12MHz (for short-distance high-speed transmission);

[0079] The channel quality is monitored in real time through a spectrum sensing algorithm, the optimal sub-band is dynamically selected, and the power spectral density is independently set in each sub-band.

[0080] An area control terminal, connected to the sensor module, receives and encapsulates the multi-dimensional sensing data through power line carrier communication, and can upload it to the central controller using a TDMA time slot allocation mechanism.

[0081] The central controller executes a dynamic area division algorithm based on the multi-dimensional sensing data to divide the independent control areas of street lamps, and sends street lamp brightness adjustment instructions according to the brightness optimization model;

[0082] The dimming drive module receives the brightness adjustment instructions transmitted through the power line and adjusts the brightness of the street lamps in the corresponding independent control area;

[0083] Among them, the multi-dimensional sensing data includes the current time, traffic flow density, pedestrian flow density, vehicle speed, vehicle classification, as well as pedestrian speed and pedestrian classification; the dynamic area division algorithm includes:

[0084] According to the spatial distribution of traffic flow density and pedestrian flow density in real time, adjacent street lamps are merged into independent control areas through clustering.

[0085] In this embodiment, at least three sensors are deployed. The sensor module includes:

[0086] The geomagnetic sensor can use the HMC1022 magnetoresistive sensor (sensitivity ±0.1μT, sampling rate 10Hz), which can be deployed every 30 - 50 meters. It can detect the magnetic field distortion caused by vehicle metal parts, eliminate the geomagnetic background noise through differential signals, and is used for vehicle presence judgment and vehicle speed estimation. It can work all-weather, is not affected by rain, snow, and light, and has a service life > 10 years;

[0087] The pyroelectric infrared sensor is used for pedestrian detection. It can sense the change in the intensity of infrared rays caused by human body heat radiation, and cooperate with the Fresnel lens to enhance the signal; it outputs the pedestrian passing frequency (times / minute) and moving direction (dual-element differential detection), and has the advantages of low power consumption (<1mW) and privacy-friendly (no image collection).

[0088] The embedded camera is used to assist in visual verification and anomaly detection of traffic flow density. The image sensor of OmniVision OV4689 can be used, which supports HDR (120dB) and has a dynamic range exceeding that of the human eye.

[0089] For the multi-dimensional sensing data, it can be uploaded to the cloud server, and a highly available cluster server is deployed to run the digital twin engine to synchronize urban multi-dimensional data in real time and synchronously access meteorological data.

[0090] The cloud server can deploy an object detection model trained based on YOLOv4, and the object detection model performs visual verification and anomaly detection according to the video data obtained by the embedded camera;

[0091] The visual verification includes: classifying and bounding the detection boxes of the target objects in the detection area through the object detection model, and determining the number of target objects according to the number of detection boxes;

[0092] The abnormal detection includes crowd gathering and traffic accidents;

[0093] The judgment rules for crowd gathering include:

[0094] The density of the pedestrian flow exceeds the specified pedestrian flow density threshold and the number of detection frames determined to be human bodies is greater than the specified number threshold;

[0095] The judgment rules for traffic accidents include:

[0096] Abnormal vehicle posture: the aspect ratio mutation > 20%;

[0097] Discontinuous movement: acceleration > 3m / s²;

[0098] Multi-target interaction: the IoU of multiple detection frames > 0.6 for 3 seconds;

[0099] If any of the above is satisfied, it is determined that a traffic accident has occurred.

[0100] By adopting the above technical solution, through the analysis and fusion of multi-dimensional sensing data, the present application can realize the dynamic grouping of street lights, thereby realizing regional dynamic dimming, can greatly reduce the redundant lighting area, reduce the running time of the lamps at full power or high power, can not only optimize the energy efficiency, but also reduce the full-life cycle operation cost of the street lights. At the same time, by communicating based on the power transmission line, on the one hand, it can reduce the line transformation cost, and on the other hand, it can greatly improve the anti-interference performance during long-distance transmission compared with the mainstream wireless communication scheme.

[0101] Optionally, the dynamic area division algorithm includes:

[0102] Obtain the geographical locations and corresponding numbers of all street lights;

[0103] Calculate the similarity between street light i and adjacent street light j within a limited area with a diameter of R ;

[0104] ;

[0105] wherein, the center of the limited area coincides with the position of street light i, is the straight-line distance between street light i and street light j, is the value of the k-th type of sensing data configured on street light i, is the value of the k-th type of sensing data configured on street light j, is the maximum value corresponding to the k-th type of sensing data, and z is the total number of types of sensing data;

[0106] Within the limited area, when the similarity is greater than or equal to the specified similarity threshold The street lamps are divided into the independent control areas.

[0107] By adopting the above technical solution, through the similarity calculation, the difference degree of the environments at adjacent street lamp locations can be determined. The greater the similarity , the smaller the environmental difference between adjacent street lamps. Therefore, the same brightness adjustment instruction should be adopted, so that it is not necessary to control each street lamp individually, reducing the control management cost and also reducing the waste of electric energy. Moreover, it can give passing cars and pedestrians a sense of the street lamps following them, ensuring the normal use of users.

[0108] Optionally, the dynamic area division algorithm includes:

[0109] Configure a specified path length , and obtain the number m of the street lamp division areas on the specified path length ;

[0110] If , then adjust the value of the specified similarity threshold until ;

[0111] Wherein, , is the minimum division number, is rounding down, is the preset standard path length.

[0112] By adopting the above technical solution, unnecessary or excessive dynamic area division numbers can be reduced, and the management and control cost can be reduced.

[0113] Optionally, the method for obtaining the brightness adjustment instruction includes:

[0114] ;

[0115] ;

[0116] Wherein, is the real-time traffic flow, is the pedestrian flow density, is the theoretical maximum traffic flow, is the theoretical maximum pedestrian flow density, , is the average vehicle speed, is the vehicle speed limit value, is the average pedestrian speed, is the theoretical maximum walking speed of pedestrians, is the preset demarcation time point, is a specified value, is the lowest reference brightness value.

[0117] In this embodiment, it can be selected as 10 o'clock at night to reflect the difference in the influence of traffic flow on brightness adjustment before and after the preset demarcation time point. By normalizing the real-time traffic flow and pedestrian flow density, and performing weighted calculations with the average vehicle speed, average pedestrian speed, and the lowest reference brightness value, the final street lamp brightness control value to be achieved is obtained ; In addition, and are both dynamic weights, inversely proportional to the illuminance, and directly proportional to the rainfall and fog index, can be positively correlated with or the noise intensity in the area where it is located, and the value range of 0.9 - 1.1 can be pre-configured. Then it can be set according to the level of the corresponding road and meteorological data. If a traffic accident is detected, needs to be increased by a specified amplitude. If a crowd gathering is detected, can be increased by a specified amplitude; if both a traffic accident and a crowd gathering are detected simultaneously, then the limit of can be exceeded, but the maximum does not exceed 1.2.

[0118] In addition, the method for obtaining the lowest reference brightness value includes:

[0119] ;

[0120] Among them, is the weather severity coefficient, is a preset dynamic coefficient function associated with the weather severity coefficient, is the reference brightness value corresponding to the road level . The weather severity coefficient can be quantitatively calculated according to meteorological data. The meteorological data includes illuminance, rainfall, and fog index. A dynamic coefficient function that is negatively correlated with illuminance but positively correlated with rainfall and fog index can be designed to calculate the weather severity coefficient . In this embodiment, a weighted method can be used, and finally, normalization (it is required that the minimum value of the weather severity coefficient is 0.8 and the maximum value is 1.4) is completed for the dynamic adjustment of the lowest reference brightness value .

[0121] Optionally, the dimming drive module adopts a hybrid dimming architecture: integrating PWM high-frequency chopping and CCR linear regulation. The lamps used for the street lamps integrate at least 4 independent LED lamp strings;

[0122] Channel 1: Color temperature is 5000K, maximum current is 1.2A, providing main road lighting;

[0123] Channel 2: Color temperature is 3000K, maximum current is 0.8A, providing warm light for the sidewalk;

[0124] Channel 3: Color temperature is 6500K, maximum current is 1.5A, providing emergency high brightness;

[0125] Channel 4: Color temperature is RGBW, maximum current is 0.5A per color, providing landscape interaction.

[0126] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. An intelligent street lamp dimming system based on power line transmission signal, characterized in that: include: The sensor module is used to acquire multi-dimensional sensor data corresponding to the street lamp position in real time; A regional control terminal connected to the sensor module, receiving and uploading the multi-dimensional sensor data via a power line; A central controller executes a dynamic area division algorithm to divide the street lamps into independent control areas according to the multi-dimensional sensing data, and sends street lamp brightness adjustment instructions according to a brightness optimization model; The dimming drive module receives the brightness adjustment command transmitted through the power line and adjusts the brightness of the street lights in the corresponding independent control area; The multi-dimensional sensor data includes the current time, vehicle density, pedestrian density, vehicle speed, vehicle classification, and personnel speed and personnel classification; the dynamic area division algorithm includes: Based on the spatial distribution of vehicle and pedestrian density in real time, adjacent street lights are merged into independent control areas through clustering; The dynamic region partitioning algorithm comprises: Get the geographic location and corresponding number of all street lights; Calculate the similarity between street lamp i and its adjacent street lamp j in a limited area with a diameter of R ; ； The center of the limited area coincides with the position of the street lamp i. is the straight-line distance between the street lamp i and the street lamp j, is the value of the kth sensor data configured on the street lamp i, is the value of the kth sensor data configured on the street lamp j, is the maximum value corresponding to the kth type of sensor data, and z is the total number of sensor data types; In the limited area, the similarity Greater than or equal to the specified similarity threshold The street lights are divided into the independently controlled areas; Configure the specified path length , get the specified path length The number of street light division areas m; like , then the specified similarity threshold Adjust the value until ; in, , is the minimum number of divisions, The default standard path length.

2. The intelligent street lamp dimming system based on power line transmission signal according to claim 1 is characterized in that: The method for obtaining the brightness adjustment instruction includes: ； ； in, is the street light brightness control value, For real-time traffic flow, is the traffic density, is the theoretical maximum traffic flow, is the theoretical maximum traffic density, , is the average vehicle speed, is the vehicle speed limit, is the average pedestrian speed, is the theoretical maximum pedestrian speed, To preset the demarcation time point, is the specified value, is the minimum reference brightness value, is a dynamic weight, inversely proportional to the illumination and directly proportional to the rainfall and fog index. To dynamically fine-tune the weights, is a natural constant, t is the current time point, , , , are the specified weighting coefficients of the corresponding items respectively.

3. The intelligent street lamp dimming system based on power line transmission signal according to claim 2 is characterized in that: The sensor module comprises: Geomagnetic sensor, used to detect vehicle presence and estimate vehicle speed; Pyroelectric infrared sensor, used to sense the change of infrared intensity caused by human body thermal radiation, and cooperate with Fresnel lens to enhance the signal; Embedded cameras to assist with visual verification of vehicle density and anomaly detection.

4. The intelligent street lamp dimming system based on power line transmission signal according to claim 3 is characterized in that: Also includes: The cloud server deploys a high-availability cluster server, runs the digital twin engine, synchronizes the city's multi-dimensional data in real time, and simultaneously accesses meteorological data, which includes illumination, rainfall, and fog index.

5. The intelligent street lamp dimming system based on power line transmission signal according to claim 4 is characterized in that: The cloud server deploys a target detection model, which performs visual verification and anomaly detection based on the video data acquired by the embedded camera; The visual verification includes: classifying the target bodies in the detection area and selecting detection frames through the target detection model, and determining the number of target bodies according to the number of detection frames; The anomaly detection includes crowd gathering and traffic accidents; The rules for judging crowd gathering include: The crowd density exceeds the specified crowd density threshold and the number of detection frames determined to be human bodies is greater than the specified number threshold; The rules for judging traffic accidents include: Abnormal vehicle posture: sudden change in aspect ratio > 20%; Discontinuous motion: acceleration > 3m / s²; Multi-target interaction: multiple detection boxes with IoU>0.6 for 3 seconds; If any of the above items is met, it is determined that a traffic accident has occurred.

6. The intelligent street lamp dimming system based on power line transmission signal according to claim 1, characterized in that: The dimming drive module adopts a hybrid dimming architecture: integrating PWM high-frequency chopping and CCR linear regulation. The lamp used in the street lamp integrates at least 4 independent LED light strings; Channel 1: color temperature 5000K, maximum current 1.2A, providing main road lighting; Channel 2: color temperature 3000K, maximum current 0.8A, providing warm light for sidewalks; Channel 3: color temperature 6500K, maximum current 1.5A, providing emergency high brightness; Channel 4: color temperature RGBW, maximum current 0.5A per color, providing landscape interaction.

7. The intelligent street lamp dimming system based on power line transmission signal according to claim 1, characterized in that: The sensor module includes a power line carrier communication module responsible for communicating with the regional control terminal using high-speed power line carrier technology HPLC; The power line carrier communication module, the physical layer supports OFDM modulation, the number of subcarriers is ≥512, the symbol rate is 10ksps, the data link layer supports TDMA / CSMA mixed access mode, and the time slot length is 100ms; The power line carrier communication module adopts adaptive frequency band switching technology, supports 0.7-12MHz full frequency band coverage, and is divided into three sub-bands: Low frequency band: 0.7-3MHz; Mid-band: 3-6MHz; High frequency band: 6-12MHz; The spectrum sensing algorithm monitors the channel quality in real time, dynamically selects the optimal sub-band, and independently sets the power spectrum density in each sub-band.

8. The intelligent street lamp dimming system based on power line transmission signal according to claim 4, characterized in that: The minimum reference brightness value The methods for obtaining include: ； in, is the weather severity factor, To preset dynamic coefficient functions associated with weather severity coefficients, For road level The corresponding reference brightness value.

Images